Facilitator Overview
The Orchus x402 facilitator runs at https://x402.agentstrail.ai. It is the trusted third party that verifies and settles USDC payments on behalf of resource servers.
What a Facilitator Does
In the x402 protocol, the facilitator sits between the resource server and the blockchain:
- Resource server receives a signed payment from the client
- Resource server forwards payment to
POST /verify— facilitator checks the signature is valid - Resource server delivers the response
- Resource server forwards to
POST /settle— facilitator submits the Solana transaction on-chain - Facilitator returns a settlement proof (transaction signature)
The resource server never touches the blockchain directly.
Endpoints
| Method | Path | Purpose |
|---|---|---|
GET | /health | Liveness + fee payer SOL balance |
GET | /supported | Payment kinds and networks this facilitator supports |
POST | /verify | Verify a signed client payment payload |
POST | /settle | Submit the Solana tx and return settlement proof |
See API Reference for full request/response shapes.
Fee Payer
The facilitator maintains its own Solana keypair (the "fee payer") that pays SOL transaction fees on behalf of clients. The client pays only USDC — no SOL needed.
Monitor fee payer balance via /health. If SOL balance drops below the configured threshold, the facilitator returns status: "degraded".
Self-Hosting
The facilitator is open source at github.com/wizardwiz706/x402-agentstrail. Run your own instance if you need:
- Custom allowed recipients (
ALLOWED_PAY_TO) - Custom rate limits
- A dedicated RPC endpoint
- On-premise key management (encrypted keypair support included)
Point your @x402/express middleware at your own URL instead of https://x402.agentstrail.ai.